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    <title>Document</title>
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    <script>
        // 创建一个函数给两个行参
        function changeNum(arr, aee) {
            // 用第三方交换法交换两个形参的值
            let a = arr
            arr = aee
            aee = a
            // return返还两个形参的值
            return [arr, aee]
        }
        let aa = changeNum(1, 2)
        console.log(aa);
    </script>
</body>

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